<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        #ball {
            background-color: red;
            width: 50px;
            height: 50px;
            border-radius: 50%;
        }
    </style>
</head>
<body>
<div id="ball" style="margin-top: 0;margin-left: 0;"></div>
<input type="button" id="btn" value="开始">
<script src="my.js"></script>
<script src="my2.js"></script>
<script>
   var a =  myFocus.set({
        clickbtn:'btn',
       ballid:'ball'
    })
</script>
</body>
</html>